Each year, tens of thousands of passengers get bumped from their scheduled flights because of overbooking. A new video from TED-Ed explains why companies do it, and why you have a right to be pissed off when it happens.

TED-Ed, with the help of gastroenterologist Dr. William D. Chey, has put together a wonderfully concise 5-minute explainer about gluten — and why it has only recently been perceived as a health problem.

Ever wonder what would happen to a deep sea fish if it swam too close to the surface, or why scuba divers have to ascend very slowly after a deep dive? The latest TED-Ed video provides the answers as it explains the physics of pressure change.

Dogs have an extraordinary sense of smell—a complex nasal architecture that lets them pick up scents and distinguish the chemical composition of hormones released by other animals. Alexandra Horowitz explains how this happens in an interesting TedEd lesson. Check it out:

The visual acuity of our canine companions is about 20-40% as good as ours. But the average dog's nose is 10,000 times more sensitive to odors than the human nose. As this fascinating TED-Ed video shows, they don't so much see the world as they smell it.

Money is just tinted paper printed with different numbers on it. So what gives the ol' greenbacks its value? The bills used to be tied to the gold standard but now, it's up to The Fed to control how many bills there are. So why can't they just decide to print out ridiculous amounts of bill to make everyone rich?

It pumps blood. Duh. Well, for most of history, people were unsure what the heart's main function was. Even Leonardo Da Vinci gave up studying it and he's probably one of the five smartest guys ever. Even now, it's not as easy as it should be to find out how the ticker works. Don't worry, this Ted-Ed animation will…

Waves come from the wind so tsunamis, which are basically bigger waves, must come from more wind, right? Not exactly. This cute animation explains that though normal waves are formed from above, tsunamis come from below from volcanic eruptions, landslides and earthquakes. They're the real monsters of the sea.

When you're shuffling a deck of cards, you're trying your best to ensure everything gets as mixed up as possible. But it turns out you might not have to try so hard. In this wonderful TedEd animation, Yannay Khaikin outlines the staggering number of ways a deck of 52 cards can be arranged.

In this newly released video from the folks at TED-Ed, educator Dennis Wildfogel teams up with animator Ash Barker to explain not only what the universe is made of, but what it took for those cosmological building blocks to get where they are today.

It might seem like a simple question, but as this TED-Ed video beautifully illustrates, the task of measuring an object's speed as it's traveling through space is far more complicated than it looks — even if you're aboard the starship Enterprise.

We know that time travel is possible, at least in the forward direction. In this recently released TEDEd video, educator Colin Stuart imagines where and when it might take us, while exploring the science behind time travel and time dilation.

Though most of us probably think time travel only works inside a DeLorean, much smarter folks out there can explain it slightly better than Doc Brown. Like this TED-Ed animation narrated by Colin Stuart. It reveals how time travel is possible, who has time traveled the longest, the history of time travel and the…

Wrinkle your brain a little bit as it tries to wrap itself around what Deja Vu actually is. This TED Education animation by Michael Molina and animated by Josh Harris tries to explain the phenomenon of deja vu.

Educator Joy Lin has teamed up with TedEducation to produce a series of fantastic animated shorts that explain the physics behind such superpowers as flight, speed, strength, invisibility, body mass manipulation, and immortality.

Current estimates put the number of stars in the Milky Way at well over 100 billion, each of which is thought to have at least one planet in its orbit. Assuming at least some of these planets have given rise to intelligent life capable of communicating with Earth, why haven't we heard from them yet?

Check out the wave-particle duality as presented by Colm Kelleher and animated by Nelson Diaz for TEDEd; it's a clever explanation to a longtime quantum conundrum. Even better: it's delivered with a lilting Irish accent — which makes the historical bit about the eye-horses that much more entertaining.